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   /*
    * Copyright 2012 The Netty Project
    *
    * The Netty Project licenses this file to you under the Apache License,
    * version 2.0 (the "License"); you may not use this file except in compliance
    * with the License. You may obtain a copy of the License at:
    *
    *   https://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   * License for the specific language governing permissions and limitations
   * under the License.
   */
  package io.netty.handler.codec.bytes;
  
  import io.netty.buffer.ByteBuf;
  import io.netty.buffer.ByteBufUtil;
  import io.netty.channel.ChannelHandlerContext;
  import io.netty.channel.ChannelPipeline;
  import io.netty.handler.codec.LengthFieldBasedFrameDecoder;
  import io.netty.handler.codec.LengthFieldPrepender;
  import io.netty.handler.codec.MessageToMessageDecoder;
  
  import java.util.List;
  
  /**
   * Decodes a received {@link ByteBuf} into an array of bytes.
   * A typical setup for TCP/IP would be:
   * <pre>
   * {@link ChannelPipeline} pipeline = ...;
   *
   * // Decoders
   * pipeline.addLast("frameDecoder",
   *                  new {@link LengthFieldBasedFrameDecoder}(1048576, 0, 4, 0, 4));
   * pipeline.addLast("bytesDecoder",
   *                  new {@link ByteArrayDecoder}());
   *
   * // Encoder
   * pipeline.addLast("frameEncoder", new {@link LengthFieldPrepender}(4));
   * pipeline.addLast("bytesEncoder", new {@link ByteArrayEncoder}());
   * </pre>
   * and then you can use an array of bytes instead of a {@link ByteBuf}
   * as a message:
   * <pre>
   * void channelRead({@link ChannelHandlerContext} ctx, byte[] bytes) {
   *     ...
   * }
   * </pre>
   */
  public class ByteArrayDecoder extends MessageToMessageDecoder<ByteBuf> {
      @Override
      protected void decode(ChannelHandlerContext ctx, ByteBuf msg, List<Object> out) throws Exception {
           // copy the ByteBuf content to a byte array
          out.add(ByteBufUtil.getBytes(msg));
      }
  }